In picture tag mode, Pixavif adds AVIF and WebP sources to the page HTML. A page cache saves that HTML. Pages cached before conversion keep showing the old images until the cache is cleared.
What to do
Array
Array
Array
New uploads are converted within a minute or two. Pages cached in that time pick up the new images the next time the cache expires.
Elementor
Elementor keeps the HTML of its widgets for up to 24 hours (Settings → Performance → Element Cache). Pixavif clears that cache when a bulk run finishes, when converted copies are removed and when you change the delivery method, so Elementor pages pick up the right images on the next visit. You do not need to do anything.
Lazy loading and optimization plugins
Pixavif keeps the lazy loading attributes of your theme and plugins. If a plugin replaces images with its own markup after Pixavif runs, switch Pixavif to server rewrite, which does not depend on the HTML.